Aiothrottle

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- Set minimum required Python version to 3.4.2, the same as aiohttp 1.0.0

- Made aiothrottle compatible with current aiohttp version again
(Now using aiohttp.StreamReader._buffer_size)

- Catching RuntimeError when trying to pause a closing _SSLProtocolTransport

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- Fixed resuming transport too often

- Added 'rate_limit' and 'throttling' properties

- Fixed buffer limit control

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- Added limit_rate() and unlimit_rate() globally and response-wise

- Raising ValueError on invalid rate limit

- Cancelling _check_handle in Throttle's destructor

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- Initial release with basic throttling functionality